Inverter-integrated electric compressors, which integrally incorporate inverter devices, are used as air conditioner compressors installed in electric vehicles, hybrid vehicles, and the like. This inverter-integrated electric compressor is configured so that high-voltage direct-current power supplied from a power source unit mounted on a vehicle is converted into three-phase alternating current power of required frequency by the inverter device, which is then applied to an electric motor so that the electric motor is driven.
The inverter device is constituted of a plurality of high-voltage electric components such as a coil and a capacitor constituting a noise removing filter circuit, a plurality of semiconductor switching elements such as IGBT constituting a switching circuit for converting power, an inverter circuit including the filter circuit and the switching circuit, and a substrate on which a control circuit of the inverter circuit is mounted, and is used to convert direct current power inputted via a P-N terminal into three-phase alternating current power and to output the three-phase alternating current power from a UWV terminal toward an electric motor. The inverter device is incorporated into an inverter housing section provided on an outer circumference of a housing of the electric compressor so that the inverter device is integrated.
A power-source-side cable for supplying direct current power from a power source to the inverter device, for example, as disclosed in Patent Literature 1, is configured to be connected, via a connector of the power-source-side cable, to a connector connecting portion provided on the inverter housing section side, and to be connected from there to the P-N terminal on the control substrate side, via a resin substrate in which a direct current power line is constituted by a terminal block and a wiring pattern, the filter circuit constituted by the coil and the smoothing capacitor provided on the resin substrate, a bus bar assembly, and the like.
Patent Literature 2 discloses a configuration in which a power source input port forming portion is formed, on a metallic inverter cover that seals an inverter housing space in which a circuit substrate is installed, the coil and the capacitor for use in the filter circuit being mounted on the circuit substrate, and a metallic terminal is resin-insert molded in the power source input port forming portion to integrally provide a resin-made power source connector, the power-source-side cable is connected to the power source connector, and the metallic terminal of the power source connector and the circuit substrate are connected by fixing the inverter cover to a housing. Patent Literature 3 discloses a configuration in which a power conversion substrate is fixed and installed in such a way that an elastic member is sandwiched between the power conversion substrate and the inner surface of a substrate cover, and the coil and the capacitor for use in the filter circuit are arranged on a surface opposing to a housing, a lower portion of the coil and the capacitor is inserted and installed into a housing-side concave portion.